Weft thread supply and storage apparatus for gripper shuttle looms



Feb. 4, 1969 l E. PFARRWALLER 3,425,462

WEFT THREAD SUPPLY AND STORAGE APPARATUS FOR GRIPPER SHUTTLE LOOMS Filed Oct. 4, 1966 SheeiI of 5 73 77@ f2 7 75 Mb .9a 77a 9 36 Fig. Z

w, 25M 1'65) 25J 251' 73a 256 44 Inventar: Ergn Pfolrrwclller ATTORNEYS Feb. 4, 1969 E. PFARRWALLER 3,425,452

WEFT THREAD SUPPLY AND STORAGE APPARATUS FOR GRIPPER SHUTTLE LOOMS Filed oet. 4, 196e sheet 2 ers ERwlN PFARRWALLER B Meij QJJL..

ATT RNEYS Feb. 4, 1969 E. PFARRWALLER WEFT THREAD SUPPLY AND STORAGE APPARATUS FOR GRIPPER SHUTTLE LOOMS.

Filed Oct. 4. '1966 Sheet 3 o' /nven tor:

Erwin Pfc rrwdller BY 61W,

MYJJWM 54....,

ATTORNEYSV 1 United States Patent() 13,750/65 U.s. C1. 139-122 Int. ci. D04b 15/48, 15/54, 27/10 7 Claims ABSTRACT OF THE DISCLOSURE For looms of the gripper shuttle type, there is disclosed a weft thread intermediate storage apparatus comprising a group of levers pivoted on a common shaft and each having a thread-guiding eye in the end thereof, means to swing alternate of these levers in opposite directions between a first or thread delivery position in which the eyes are aligned in a row parallel to the cornmon shaft and a second or thread storage position in which the eyes are not so aligned, the eyes of odd numbered of the levers being for example aligned at one position circumferentially of the common shaft while the eyes of even numbered ones of the shafts are aligned at a second position circumferentially of the common shaft, and a -bar adjustably fixable either parallel or inclined to but coplanar with the common shaft and at a variable spacing therefrom and over which a thread will be stretched in passing through the eyes of successive ones of the levers when they are swung to their second position.

The present invention pertains to weft thread supply and storage apparatus for gripper shuttle looms in which the weft supply bobbin remains outside the shed. More particularly, the invention pertains to apparatus of this type in which there is disposed between the weft thread supply bobbin and the picking mechanism from which the shuttle is shot into the shed a plurality of weft thread guide levers having thread eyes at the ends thereof, disposed one behind the other on a common shaft and periodically movable in reciprocating fashion transversely of the weft thread path. The levers move between an aligned position for picking, in which their eyes are aligned with each other (and, preferably, substantially aligned with the fiight path of the shuttle), and a thread storage position in which successively adjacent levers are swung in opposite directions so as to define a zigzag path between the thread eyes of the levers.

The invention provides apparatus of this character in which the levers are so shaped that when their eyes are aligned, they accommodate a bar or similar member between the levers of the group which for thread storage swing in one sense and those which swing in the other sense. This bar may extend substantially parallel to the path defined by the thread eyes on the levers when aligned, and by its presence there is effected an increase in the amount of thread stored in the zigzag paths between the thread eyes when the levers are swung out to thread storage position. Specifically, the thread in passing from the eye at the end of one lever, swung clockwise, say, to the eye of the adjacent lever, swung counterclockwse, must pass over the bar and thereby follow between the eyes of those two levers a broken path which is longer than the separation of those two eyes when the levers are thus swung out to thread storage position. The invention thus provides means to divert the yarn from a straight path between the eyes on adjacent levers 3,425,462 Patented Feb. 4, 1969 rice in thread storage position and this diverting means not only increases the storage capacity but helps to keep the successive segments of the stored thread neatly apart and free of tangles. Alternatively, a given linear thread storage capacity can by means of the invention be obtained with a smaller number of levers.

In one embodiment of the invention, two groups of weft thread guide and storage levers are provided, each having a thread-diverting bar and each supported on a separate common shaft, and each drawing thread from a separate supply bobbin. The levers of one group are in aligned position during a first picking operation in which the thread previously stored on the levers of that group is inserted by a shuttle into the shed, while the levers of the other group move to the swung-out thread-storage position so as to pull thread off the bobbin associated therewith and to store on the levers of that other group a length of thread sufficient for the next pick. For that next pick, the levers of the second group move to aligned position while the levers of the first group move to the swung-out thread-storage position, and so on.

In a preferred embodiment of the invention, whether one or more than one group of thread guide and storage levers is provided, the diverting bar of each such group is movable and adjustably fixable transversely of its length. The detour or extension in the thread storage path length between the eyes of adjacent levers produced by the bar can thereby be changed equally as to all pairs of adjacent levers. Means may be provided to permit continuous adjustment of the transverse position of the bar. Alternatively, the transverse adjustment of the bar may be effected in stepwise fashion by the provision, at each end of the bar, of a support having a plurality of notches therein after the fashion of a comb. With such a construction it is unnecessary to provide for variation in the angular throw of the thread guide and storage levers for variation in the amount of thread to be stored or to provide, for the same purpose, plural eyes at different distances along the levers from their axis of rotation.

Further according to the invention, means may be provided to permit adjustment of the thread-diverting bar to positions in which its two ends are at unequal distances from the axis of rotation of the thread guide and storage levers. In such embodiments, the bar effects at opposite ends of the array or group of levers, unlike increases in the thread storage capacity between the eyes of adjacent levers over the capacity which would exist in the absence. of the bar.

Preferably, the drive to the thread guide and storage levers is such that the eyes of any two adjacent levers in moving from their aligned position to their thread storage position swing through arcs which total more than With the yarn-diverting bar of the invention, such large angular excursion of the levers is made possible and useful, with consequent still further increased thread storage capacity for the intermediate weft thread storage and supply apparatus which the levers, their drive and the thread-divertin g bar together constitute.

The invention will now be further described in terms of a number of non-limitative exemplary embodiments and with reference to the accompanying drawings in which:

FIG. 1 is a diagrammatic general view of a gripper shuttle loom incorporating intermediate weft thread supply and storage apparatus according to the invention, the loom being seen from the cloth end thereof;

FIG. 2 is a view in plan at an enlarged scale of the left end of the loom of FIG. l, illustrating one embodiment of the intermediate weft thread storage and supply apparatus of the invention;

FIG. 3 is a fragmentary view similar to that of FIG. 2

but s-howingra modified construction for the thread-dl- Y Y verting bar;

FFIG. 4 is a sectional view taken on the line IV-IV in FIG. 2; and

FIG. 5 is a diagram illustrating still another embodiment of the invention.

The gripper shuttle loom shown in FIG. 1 comprises a loom frame including a central cross member 1 and two upright side members 2, 3 secured thereto. An electric motor 4 drives the loom through a belt drive 5. Also visible are a combined clutch and brake device 6, a manual adjustment handwheel 7 which acts on the loom main shaft 8, a catching mechanism 9 which receives a shuttle 11 (FIG. 2) picked from a shuttle picking station 11a (FIG. l) and which can be moved to the right in FIG. 1, for example to a position 9a, to suit the cloth width, heddles 12 and a shuttle picking mechanism 13. The heddles 12 are driven by a cam mechanismv 14. A bobbin frame 15 is mounted on the upright 2 and carrier four bobbins at the corners of a rectangle. Three of the bobbins can be seen at 21, 22, 23 in FIGS. 1 and 2 and the other bobbin is disposed below the bobbin 23 as viewed in FIG. 2. At any given time either the upper two bobbins or the lower two bobbins are in use while the other two bobbins are in reverse. Weft yarns 16, 16a are drawn off the bobbins and go via a weft storage device 17 according to the invention, to the shuttle 11.

The storage device 17 comprises two groups 25, 26 of rocking levers 25a-, 26a-i. The levers of the group 25 are pivotable around a spindle 28 and the levers of the group 26 are pivotable around a spindle 29. The group 25 is shown in FIG. 2 in the yarn-delivering position, i.e. with the free ends of its levers aligned, and the lever group 26 is shown in FIG. 2 in the yarn-storage position with the free ends of adjacent levers swung successively clockwise and counterclockwise from each other, as illustrated in FIG. 4. The direct path taken by the yarn is shown for the group 25 and has the reference 16b. A thread storage brake 31 is `disposed between the group 25 and the bobbin 23, and a thread storage brake 32 is similarly disposed upstream of group 26 in the sense of thread motion. A stationary eye 55 and a thread feed tube 35 are provided between the levers of group 25 and the picking position for the shuttle 11. Correspondingly, the other weft yarn 16a passes from the levers of the group 26 to to a stationary eye 56 and to another thread feed tube which is disposed below the tube 35. One of two weft feeders supplies the weft thread leaving the tube 35 to the shuttle 11 which grips the thread.

The two weft feeders are guided by a weft changing element 39 which is pivotable around a spindle 38 and which is driven by a cam on a camshaft 44, to be described hereinafter, in synchronism with the operation of the two lever groups 25, 26 so as to bring one of the two weft feeders into the picking line each time one of the lever groups takes up the aligned condition shown in FIG. 2 for group 25. Disposed between the weft changing element 39 and the shuttle 11 are shears 41 and other means (not shown) for gripping the yarn, more particularly a selvedge thread clamp for gripping the end of the picked weft thread after cutting, and a thread-centering system.

The main shaft 8 (FIGS. 1, 2) drives a camshaft 44 (FIGS. 2, 3) via gearing 42, 43 producing a two to one reduction so that the camshaft 44 runs at half the main shaft speed. Nine cam pairs 46, 47 are secured to the shaft 44 as indicated in FIG. 4. Each cam pair drives, Via a pair of roller levers 48 and 48a and through a pair of links 49 and 49a, one pair of adjacent levers such as the levers 25b and 25C in the group 25. That pair of cams 46 and 47 also drives, via a second pair of roller levers 53 and 53a and through a pair of links 54 and 54a, a pair of adjacent levers such as the levers 26h and 26e in the group 26.

The levers of each group are thus divided into two subgroups, the levers of one sub-group being swung for thread storage in one sense from the aligned position shown for the group 25 in FIG. 2 and the levers of the other sub-group being swung in the opposite sense. Counting along either of the lever-supporting shafts 28 or 29, even numbered ones of the levers 25a-i belong to one sub-group and odd numbered levers belong to the other sub-group, and similarly in the case of the levers of group 26. The levers are so shaped, as appears from the levers 25a and 25b of group 25 as seen in FIG. 4, that when their thread-guiding eyes are aligned with each other for thread delivery, an open space is left between the levers of the two sub-groups. Moreover, when the levers swing to thread storage position, they swing so as to enlarge this open space.

In accordance with the present invention the storage capacity of the lever system is increased by mounting a bar, shown at 73 for the lever group 25 and at 73 for the lever group 26, which extends between the two sub-groups of levers in each group. By virtue of the provision of this bar, the thread storage capacity is increased, and can be made variable for a given angular throw of the levers by adjustment of the position of the bar toward or away from the pivotal axis at 28 or 29 of the lever group 25 or 26 to which the bar belongs.

Each of the thread-diverting bars 73 and 73 is supported at both ends of its respective one of the groups of levers 25 and 26 from the frame members 85 and 86 (FIG. 2) which support the stationary thread tensioning brakes 31 and 32 and the stationary eyes 55 and 56.

Thus as illustrated in FIG. 2, support members 87 and 88 are afxed to the members 85 and 86 for support of the diverting bars 73 and 73 at the end of the intermediate weft thread storage apparatus adjacent the shed. It will be seen from the lower half of FIG. 2 how the bar 73 lengthens the path over which the thread 16a extends between the two axially adjacent, oppositely swung-out thread guide and storage levers 26aby comparison with the direct separation of the ends of those levers.

The support members 87 and 88 (FIG. 2) may be extended radially of their respective associated shafts 28 and 29, and include means permitting the bars 73 and 73' to be xed in various positions, at various distances from those shafts 28 and 29, and with the bars 73 and 73' either parallel or inclined to those shafts. This is illustrated in FIG. 3 where the reference character 73b shows a position for the bar 73 parallel but close to the shaft 28, while reference character 73a shows for that bar a position oblique to that shaft. The farther the bar from the axis of pivotal rotation of the levers with which it c0- operates, the greater the increase in storage capacity effected by the bar. Thus in FIG. 3 with the bar 73 in the oblique position indicated at 73a, the bar will effect a large increase in the thread storage capacity of the pair of adjacent levers 25a and 25b, and a smaller increase in the thread storage capacity of the pair of adjacent levers 25h and 251'.

FIG. 5 illustrates another embodiment of the invention wherein a pair of axially adjacent thread guide and storage levers 25a and 25b is shown in full lines in swung-out, thread-storage position. Another pair of axially adjacent :levers 25j and 25k of the same group is shown, in dashed lines, in aligned position, aligned with the xed thread eye 55 at the shed side of the intermediate weft thread storage and supply apparatus. It will be appreciated that when the levers 25a and 25b are in the swung-out position as illustrated in FIG. 5, the levers 25j and 25k are in swung-out position also. It is for this reason that the levers 25]"and 25k are shown in chain lines in FIG. 5. All of the levers of a single one of the groups 25 and 26, i.e. all of those mounted on the shaft 28 in FIG. 5, move together and in phase between the swung-out, thread storage position exemplied in FIG. 5 by the showing of levers 25a and 25b and the swung-in, thread delivery position exemplified in FIG. 5 by the chain line showing of levers 25j and 25k.

Each of the weft thread guide and storage levers (e.g. 25a, 25b, 25j, 25k) is driven by a separate rack 78 meshing with a gear sector 79 on that lever in order to rotate the lever between aligned and swung-out positions. The racks 78 are driven in synchronism with the loom operation by means not shown, the racks of axially adjacent levers moving in opposite directions. The thread-diverting bar is shown in one position at 73 and in another position closer to the axis of rotation of the levers at 73b. A plate 83 having notches 81 aligned along a radius from the axis of rotation of the levers is provided at each end of the assembly, a single such plate being seen in the figure. One end of the bar 73 can be received in any one of the notches 81 at one end of the assembly, While the other end of the bar can be received in any one of the notches 81 at the other end of the assembly.

FIG. 4 clearly shows how, with the thread-diverting bar of the invention, the levers may be swung through arcs aggregating over 180 (the angle A in FIG. 4) for any pair of adjacent levers to provide a large thread storage capacity without danger that the thread will become fouled at the roots of the levers where they are pivoted for rotation. FIG. 4 also shows particularly by means of the levers 25j and 25k there illustrated, how an open space is left between those levers when their eyes 77 are aligned with each other so as to accommodate the thread-diverting bar 73.

The thread-diverting bars 73 and 73 which serve to space the thread from the axes of rotation of their associated groups of levers may have smooth surfaces, or they may be provided with a rough surface as for example by means of a coating of felt or plush.

While the invention has been described hereinabove in terms of a number of presently preferred embodiments, the invention itself is not limited thereto, but comprehends all modifications of and departures from those embodiments falling within the spirit and scope of the appended claims.

I claim:

1. Intermediate weft thread storage and supply ap- 4 paratus for gripper shuttle looms, said apparatus comprising a plurality of coaxial levers each having a threadguiding eye therein, means to rotate adjacent of said levers in mutually opposite directions about the axis in which said levers are coaxial between a thread delivery position in which said eyes are in substantial alignment at one location circumferentially of said axis and a thread storage position in which the eyes of adjacent of said levers are angularly displaced with respect to each other about said axis, and thread spacing means extending lengthwise of and spaced from said axis adjacent said one location circumferentially of said axis to space away from said axis a thread passing through said eyes when said levers are in said thread storage position.

2. Apparatus according to claim 1 including two pluralities of coaxial levers, and means coupling said pluralities of levers together for motion in opposite phases as between thread delivery and thread storage positions.

3. Apparatus according to claim 1 including means to adjust radially of said axis at least one end of said thread spacing means.

4. Apparatus according to claim 1 wherein said thread spacing means has a rough surface.

5. Apparatus according to claim 1 wherein the sum of the angles through which two adjacent of said levers are rotated between thread delivery and thread storage positions is greater than 180.

6. Apparatus according to claim 1 including a separate rack and pinion drive for each of said levers.

7. Apparatus according to claim 1 wherein adjacent of said levers are curved circumferentially of said axis in opposite directions to define when in thread delivery position an open space for reception of said thread spacing means.

References Cited UNITED STATES PATENTS 2,005,975 6/1935 Javery et al 242-154 3,330,304 7/1967 Hall 139-122 FOREIGN PATENTS 5 82,066 9/ 1958 Italy. 592,969 10/ 1947 Great Britain.

HENRY S. JAUDON, Primary Examiner. 

